Engine exhaust structures are conventionally known that include a muffler and a mist separator (gas-liquid separator) on the exhaust path of a stationary engine (see, for example, Patent Document 1). The engine exhaust structure described in Patent Document 1 includes a muffler 102, a mist separator 105, a drain filter 107, and a drain water recovering tube 108 as illustrated in FIG. 10. The muffler 102 is spatially continuous with an exhaust gas hose 101 of the engine 100. The mist separator 105 is spatially continuous with the muffler 102 via an exhaust gas pipe 103. The drain filter 107 is spatially continuous with the muffler 102 via a muffler drain tube 106. The drain water recovering tube 108 is spatially continuous with the drain filter 107 and the mist separator 105.
In this structure, the exhaust gas that rises from the muffler 102 via the exhaust gas pipe 103 is released outside after the exhaust gas is rid of water in the mist separator 105. The mist separator 105 accumulates the removed water (condensed water). The condensed water accumulated in the mist separator 105 is recovered in the drain filter 107 via the drain water recovering tube 108.
Another known engine exhaust structure includes a mist separator that is modified for improved capability of capturing condensed water in the exhaust gas (see, for example, Patent Document 2). Patent Document 2 discloses a structure where the exhaust outlet tube has a downstream end thereof inserted into the mist separator and also has an insertion section on which there is provided a groove section that curves outward.